If this is accurate, and it holds, it's about in line with what people are expecting. Piper Jaffray analyst Gene Munster says investors are expecting about 37.5 million iPhones for the first quarter.

If Apple sells 37 million iPhones, it's 5% year over year growth, which is not strong. In last year's March quarter, iPhone unit growth was 88%. (iPhone unit growth is expected to be ~30% on a year over year basis for the holiday quarter.)

This is the big concern for Apple. Pacific Crest recently issued a report saying the market for the iPhone as Apple currently sells it is reaching a saturation point. Only so many people around the world can afford the iPhone. If growth falls to 5% it would confirm the biggest fear of investors.